Single Idea 14447

[catalogued under 4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V]

Full Idea

The Axiom of Infinity may be enunciated as 'If n be any inductive cardinal number, there is at least one class of individuals having n terms'.

Gist of Idea

Infinity says 'for any inductive cardinal, there is a class having that many terms'

Source

Bertrand Russell (Introduction to Mathematical Philosophy [1919], XIII)

Book Reference

Russell,Bertrand: 'Introduction to Mathematical Philosophy' [George Allen and Unwin 1975], p.131


A Reaction

So for every possible there exists a set of terms for it. Notice that they are 'terms', not 'objects'. We must decide whether we are allowed terms which don't refer to real objects.

Related Idea

Idea 15931 The iterative conception needs the Axiom of Infinity, to show how far we can iterate [Lavine]